Topic: Easy switching between unbalanced and balanced inputs on 2/4?

Problem:

I want to change the Analogue Inputs very frequently on my 2/4 Pro SE, like at least once or twice a day, between my Turntable, and my stereo Mic Pre/DI. I like listening to records AND practising electric guitar through amp sim plugs, each and every day. smile

Right now I have to get round the back of the 2/4 and swap the phone plugs and the XLRs in the combo jack (Input 1/2).

Does anyone have an elegant solution that would allow me to more easily swap the inputs, without the expense and hassle of a mixer or a patch bay? Any kind of cable harness or switch box that would allow me to switch inputs from the front side, more easily etc?

Thanks in advance for any solutions. If not then I might just have to resign myself to the constant swapping...

https://musicwall.app/hermetech

2 (edited by KaiS 2022-12-30 20:40:09)

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Turntable MM-Pickup signals are very dependent on proper capacitive load.
Running through a switchbox and extra cables can decrease sound quality.


If this is not a problem, use one of these with as short cables (for the turntable’s signal path) as possible:
Use low capacitance cables, specially the longer one between turntable and switchbox, if possible.
Lowest have 35-40 pF/m.


https://smile.amazon.de/Nobsound-1-Ausg … amp;sr=8-3
https://m.media-amazon.com/images/I/71A1QxAFApL._AC_SX679_.jpg

PLUS: https://smile.amazon.de/Stecker-Profess … amp;sr=8-3
https://m.media-amazon.com/images/I/71UJAGmOjdL._SX522_.jpg




————————-—- OR: —————————
(With probably more internal cabling and more turntable signal degradation)

https://smile.amazon.de/Nobsound-Balanc … mp;sr=8-36

https://m.media-amazon.com/images/I/719yGZOPdgL._AC_SX679_.jpg

https://m.media-amazon.com/images/I/41UAj1uG0xL._AC_.jpg

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Thanks, I'll have a think about those. The problem is I still want the TT to go in unbalanced, and the DI to go in Balanced. Not sure how to "fan out" the two separate inputs on the Neutrik Combo socket for Analogue 1/2 on the back of the RME.

https://musicwall.app/hermetech

4 (edited by KaiS 2022-12-31 00:15:24)

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Babaluma wrote:

Thanks, I'll have a think about those. The problem is I still want the TT to go in unbalanced, and the DI to go in Balanced. Not sure how to "fan out" the two separate inputs on the Neutrik Combo socket for Analogue 1/2 on the back of the RME.

This is simple:

You are using very short XLRf->XLRm patches between the switchbox(#1) out and ADI-2/4 in.

The turntable is connected to the adapters, then to input X, they care for the correct wiring scheme unbalanced signal->balanced input.
This is exactly the same wiring like the use of RCA ->1/4 TS adapters directly at ADI-2/4.

https://m.media-amazon.com/images/I/71eBoLO4PSL._SX522_.jpg

The DI goes with standard XLR cable to the switchbox input Y.
It’s signal stays balanced all through then.



If you’d use switchbox(#2) the RCA adaption is built in, but I think #1 can be expected being better signal quality due to lower internal capacitance.

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Thanks for taking the time to explain, I get it now. I think I'll probably try the switchbox #2 as it seems to be exactly what I need and a more elegant solution.

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Just wanted to report back, I got the second Little Bear box KaiS recommended above, about a week ago. It works, BUT there is often a lot of crackly noise like DC leakage present when touching/moving/switching either of the two main switches. I'm going to take a look inside and maybe re-solder some of the switch connections if it looks like an easy job, but buyer beware, it's cheap Chinese crap and acts as such, at least in my case. I have yet to decide whether to send it back or not.

If you are soldering savvy it'd probably be best to build your own with Neutrik connectors and Elma switches etc. I might actually research doing just this as I don't need the multiple outputs (only Balanced XLR out to RME Input 1/2), just two switched inputs (unbalanced RCA from turntable and balanced XLR from stereo mic pre).

Having said that, I did find a load of reviews on the ASR forum of this and similar boxes from Little Bear and they appeared to test great, but they were mainly only switching balanced XLR to balanced XLR or phono to phono, not one to the other, which perhaps might be the difference here? I could have just got a bad unit.

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

One of the reasons I suggested the other “Little Bear”:
Signal runs through one switch only.

Why bother, I’d just order a replacement, until they deliver a working unit.
Kick them in the ... to make them learn their lesson smile

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Yeah I might swap it out for the first box you posted, but those XLR to Phono adaptors are not available on Amazon UK or Amazon Italia. But TBH don't really wanna risk another crappy switch box... Will take a look at the internals soon as I'm in the middle of completely re-cabling the studio with Ghost cable and Neutrik connectors.

https://musicwall.app/hermetech

9 (edited by KaiS 2023-01-10 10:45:30)

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Babaluma wrote:

...but those XLR to Phono adaptors are not available on Amazon UK or Amazon Italia.

You can order from Amazon Germany.
If you have Prime I think there’s no additional shipping cost.

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Thomann offers some nice and inexpensive Cordial branded xlr to rca cables to Italy as well.

Cheers, Ernst

ADI-2 PRO FS R BE / ADI-2 DAC FS - K371 - K712

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Cheers, I'll have a think about it!

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

I use these for connecting my single ended phono pre to my ADI2PRO:

https://www.thomann.de/de/cordial_cfu_09_pc.htm

Even they are rca to 6.3 mm ts plug.

Cheers, Ernst

ADI-2 PRO FS R BE / ADI-2 DAC FS - K371 - K712

13 (edited by KaiS 2023-01-10 23:11:01)

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Always keep cable capacitance as low as possible for phono MM-cartridges.
One of the few occasions where cables REALLY make a difference.

Total capacitance, adds up from:

   turntable’s internal cable
+ turntable’s external cable (often permanently mounted)
+ switchbox (in this case only)
+ patch cable (in this case only)
+ ADI-2/4 input (150 pF)
should be less than 300 pF.

An unspecified cable is not very well suited for the task.

Best if the turntable’s external cable can be replaced.
Well suited cables have 30-40 pF per meter.
Standard cables have 120 and more pF per meter and are unsuited.

I’d buy a capacitance meter and check (with headshell/pickup removed).

Example:
https://www.amazon.de/-/en/dp/B083V7HYJ … 226a366405

https://m.media-amazon.com/images/I/81FerYa3HsL._SX522_.jpg

Re: Easy switching between unbalanced and balanced inputs on 2/4?

emeissl wrote:

I use these for connecting my single ended phono pre to my ADI2PRO:

https://www.thomann.de/de/cordial_cfu_09_pc.htm

Even they are rca to 6.3 mm ts plug.

I understand the required cables and adaptors of course. But then I can't have the XLR plugged in at the same time, which is the whole point of this thread, being able to switch effortlessly between unbalanced RCA and balanced XLR input.

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

KaiS wrote:

Always keep cable capacitance as low as possible for phono MM-cartridges.
One of the few occasions where cables REALLY make a difference.

Total capacitance, adds up from:

   turntable’s internal cable
+ turntable’s external cable (often permanently mounted)
+ switchbox (in this case only)
+ patch cable (in this case only)
+ ADI-2/4 input (150 pF)
should be less than 300 pF.

An unspecified cable is not very well suited for the task.

Best if the turntable’s external cable can be replaced.
Well suited cables have 30-40 pF per meter.
Standard cables have 120 and more pF per meter and are unsuited.

I’d buy a capacitance meter and check (with headshell/pickup removed).

Example:
https://www.amazon.de/-/en/dp/B083V7HYJ … 226a366405

https://m.media-amazon.com/images/I/81FerYa3HsL._SX522_.jpg

Thanks for all the info and suggestions, but it's not really an issue in this case as (aside from the crappy switch box's noisy, DC leaking switch itself) I notice zero difference in sound going direct or via the switch box. It's adding just the box's internal wiring (centimetres) plus less than half a meter of balanced Ghost cable.

I have a heavily modded Rega RP6 turntable, but the cable can't be changed without internal unsoldering, and I've always been happy with the sound, so no need to change it. I have a Fluke 115 DMM which I think does capacitance readings, but like I said, no need to check as no perceivable difference in sound quality (ATC monitors in a treated room) with or without the box and minimal extra cabling.

All OT really, I'll report back when I've had a look inside the Little Bear and decided what to do about it. I'm tempted to gut it and buy an Elma switch and Neutrik connectors instead and build my own, rather than risk another disappointment with another crappy box from Little Bear.

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Somehow I lost your needs (switchbox) and was focused on my setup. Better follow one of the other proposals. Cheers

Cheers, Ernst

ADI-2 PRO FS R BE / ADI-2 DAC FS - K371 - K712

17 (edited by KaiS 2023-01-11 10:55:01)

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Babaluma wrote:

I'm tempted to gut it and buy an Elma switch and Neutrik connectors instead and build my own, rather than risk another disappointment with another crappy box from Little Bear.

You could even mod the MC 103 Pro version Little Bear with these ones, less effort than building from the scratch:
https://www.thomann.de/it/neutrik_nf2db … gIuQPD_BwE
https://www.audiophonics.fr/21483-large_default/embase-rca-pour-emplacement-xlr-blanc-unite.jpg

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Yeah but I don't think it's the connectors that are the problem really, it's the switch itself. You get horrible crackling whenever you even lightly touch the knob, even worse when you use the switch, sounds like DC leaking through.

https://musicwall.app/hermetech

Re: Easy switching between unbalanced and balanced inputs on 2/4?

Babaluma wrote:

Yeah but I don't think it's the connectors that are the problem really, it's the switch itself. You get horrible crackling whenever you even lightly touch the knob, even worse when you use the switch, sounds like DC leaking through.

That’s not DC, but a bad mechanical contact not doing it’s job (not enough contact pressure).

Bad luck maybe, the One Little Bear stuff usually works.
Claim your warranty and throw the thing into their face.